2002-05-30 04:00:00 PDT Subic Bay, Philippines -- Although some of the world's most extensive coral reefs are found in the Philippines, they are under such sustained assault by dynamite fishing that marine biologists say the corals are on the verge of utter collapse.

"There are many horrific things going on in the world's oceans, but this tops the list," said John McCosker, the chairman of aquatic biology at the California Academy of Sciences in San Francisco. "When divers talked about the world's finest coral reefs 20 years ago, the consensus for the top spot was always the Philippines, but nobody feels that way now."

Coral reefs constitute vital ecosystems for fisheries and wildlife and are even a source of medicine. Chemicals extracted from a Caribbean reef sponge are used in AZT, a treatment for AIDS.

Few places offer a more sobering example of the impact of dynamite fishing than the waters off this former U.S. naval base -- an area that once supported luxuriant corals just a few years ago.

An expatriate diver who prefers the pseudonym "Billy" because of several unpleasant run-ins with dynamiters recently took a Chronicle reporter on a tour of one of Subic's devastated reefs.

"Ten years ago, this area just teemed with fish," Billy said. "Now -- well, you'll see."

He donned his scuba gear, tipped backward from the gunwales of his dive boat and descended through the pellucid, warm water. The reef could be seen as a dark, mottled mass 60 feet below.

There were a few small fish -- some fusiliers, a lone batfish. But there were none of the big groupers and ponderous snappers and gigantic manta rays normally associated with these waters.

And there was no coral -- no living coral, at least. There were only piles and drifts of dead coral rubble littering the rocks and sand.

REEFS BECOMING DESERTS

The reef, which had been growing bit by bit for centuries, had been blasted into oblivion within a few months along with vast populations of fish, lobster,

giant clams, shrimp and sea turtles that depended on corals for food and shelter.

Back in the boat, Billy gestured toward the west shore of the bay. "It's the same way -- the corals are completely gone. Every night you hear them blowing up the reef so they can get a few fish -- boom, boom," he said. "It's turning the reefs into deserts."

According to a U.N. survey last year, the world's coral reefs -- 113,720 square miles spread among 101 countries and territories -- are declining rapidly because of dynamite and cyanide fishing, pollution and climate change.

The state of coral reefs in Southeast Asia is particularly grim.

A report released in February called "Reefs at Risk: Southeast Asia" by the World Resources Institute and the United Nations Environment Program, showed that 90 percent of reefs in Thailand, Cambodia, Singapore, Taiwan, Vietnam and China are threatened, while 85 percent are at risk in Malaysia.

The report also said the major reef nations of Indonesia and the Philippines, which contain 77 percent of the region's coral reef systems, are in deep trouble. While 86 percent of Indonesia's reefs are seriously threatened by human activities, the figure is a whopping 98 percent in the Philippines.

Dynamite -- or, more commonly, plastic bottles filled with an explosive nitrate and diesel fuel mixture -- began gaining widespread popularity among Filipino fishermen about 15 years ago, Billy and other critics say.

But the issue didn't gain global attention until the mid-1990s, forcing the Philippine government to pass stiff legislation against dynamite fishing. Critics, however, say the law has not been vigorously enforced and note destruction in some areas has even accelerated.

FISHERMEN, INDUSTRY BLAMED

Although he is frustrated with local fishermen, Billy puts most of the blame for the destruction on a lack of government oversight, upscale tourist hotels and restaurants that demand fresh seafood, and fish markets in Hong Kong and Singapore that pay premium prices for fresh fish.

McCosker, however, said fishermen also warrant vigorous condemnation.

"These aren't poor Third World guys trying to put protein on the table," he said. "Go to the villages, and you'll find the people who head the dynamite fishing cooperatives are the people with the new Jeeps and the new satellite dishes on their houses. This is about greed."

There are sanctioned marine preserves in the Philippines, most notably the Tubbataha Reefs, an 82,000-acre coral system east of Palawan Island that was declared a United Nations World Heritage Site in 1993.

An international destination for marine scientists, amateur naturalists and recreational divers, Tubbataha is home to 269 coral species, 329 fish species and eight marine mammal species.

But the reefs' remoteness, biological richness and scant state oversight make them particularly vulnerable to dynamiters.

"The entire reef is protected by a few Philippine Coast Guard guys and a little boat," said Larry Sardelli, a Florida resident who dives throughout the Philippines. "There are fishermen who come all the way from Vietnam and China to bomb the reef, because they know it's so rich. It's tragic. "

Government officials acknowledge the magnitude of the problem and say they are working to contain it.

Delos Santos says his government faces two major problems: a limited budget and 7,000 islands to patrol.

"The national government simply doesn't have the money to monitor all the reefs," he said. "So partnerships with local governments are crucial, and we could also use international aid."

CIVILIANS GUARD CORALS

Indeed, civilian patrols have helped reduce dynamiting in some communities.

Extravagant coral gardens are a hallmark of Puerto Galera, a tiny settlement on the island of Mindoro that hosts 25 dive shops. Here, resident and visiting divers act as security guards for the coral.

"We're right on top of the reefs here, and if there's a problem, we know about it," said Simon Birtles, an instructor for Action Divers at Sabang Beach near Puerto Galera. "We work with the local town officials to keep the dynamiters out. Plus, the townspeople realize their livelihoods are wrapped up with the corals. They make a lot more money (on the dive trade) than they do fishing."

Tourism director Delos Santos agreed that more state oversight is necessary to save the reefs and suggested that beefed-up patrols could be supported through fees charged to divers and other tourists.

Private funding also can contribute significantly to reef preservation, said Duane Silverstein, the executive director of Seacology, a Berkeley group dedicated to the preservation of tropical ecosystems.

"In Fiji, we built a community center in exchange for a no-take marine reserve," Silverstein said. "It's working there, so it could also work in the Philippines."

But while scientists say such projects are laudable, they also say large forces of well-trained law enforcement officials would be even better. Recent events suggest that dynamiting slackens in direct proportion to the number of cops on the water.

"I've seen tremendous changes at Sabah in eastern Malaysia near the Philippines, where Muslim guerrillas kidnapped some divers a couple of years ago," said Lauretta Burke, a senior associate with the World Resources Institute. "After the kidnappings, the government moved the navy and police out there in force, and the kidnappings stopped. The destructive fishing has been almost completely curtailed."

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